Hand lever metal punch

ABSTRACT

A hand lever metal punch capable of cutting or deforming heavy gauge metal is disclosed having a head casting fixedly mounted on a handle, a die holder pivotally mounted in the head casting and provided with a die that cooperates with punch mechanism on the head casting, and a manually actuated lever handle pivotally connected to the head casting. A cam is pinned to the lever handle, and both cam and lever handle are pivotally connected to the head casting for lifting one end of the die holder to thereby move the die carrying end of the holder into metal cutting or deforming position toward the punch mechanism when the lever handle is moved toward the punch mechanism when the lever handle is moved toward the head casting handle; the cam engaging a tongue on the die holder for raising the die carrying end of the holder and spacing it from the punch mechanism when the lever handle is moved away from the head casting handle. The manually actuated lever handle travels a substantial distance for transmitting a short powerful cutting or deforming movement of the die holder at the end of the stroke, whereas a relatively short handle movement results in spacing the die holder from the punch mechanism for reception of metal sheets or channels between them.

Unite States Patent [191 Hartmeister Oct. 22, 1974 HAND LEVER METAL PUNCH [22] Filed: June 18, 1973 [21] Appl. No.: 370,988

Primary Examiner-C. W. Lanham Assistant Examiner-Gene P. Crosby Attorney, Agent, or FirmBertha L. MacGregor [57] ABSTRACT A hand lever metal punch capable of cutting or deforming heavy gauge metal is disclosed having a head casting fixedly mounted on a handle, a die holder pivotally mounted in the head casting and provided with a die that cooperates with punch mechanism on the I head casting, and a manually actuated lever handle pivotally connected to the head casting. A cam is pinned to the lever handle, and both cam and lever handle are pivotally connected to the head casting for lifting one end of the die holder to thereby move the die carrying end of the holder into metal cutting or deforming position toward the punch mechanism when the lever handle is moved toward the punch mechanism when the lever handle is moved toward the head casting handle; the cam engaging a tongue on the die holder for raising the die carrying end of the holder and spacing it from the punch mechanism when the lever handle is moved away from the head casting handle. The manually actuated lever handle travels a substantial distance for transmitting a short powerful cutting or deforming movement of the die holder at the end of the stroke, whereas a relatively short handle movement results in spacing the die holder from the punch mechanism for reception of metal sheets or channels between them.

9 Claims, 5 Drawing Figures 1. HAND LEVER METAL PUNCH This invention relates to a hand lever metal punch capable of cutting holes in heavy metal such as 16, 18 and 24 gauge metal sheets or channels. In building construction where metal channels may be connected to each other in surface contacting relationship, it is necessary to cut through two-layers of metal which are contacting parts of two connected channels. The metal punch of my invention is capable of cutting through two layers of 16, 18 or 24 gauge metal. The punch mechanism may comprise a die and punch for cutting holes in metal or may employ a crimping tool or other metal deforming means for various purposes.

The main object of the invention is to provide a metal punch manually operable by persons of average strength, having the capability aforementioned of cutting holes in heavy gauge metal by means that include a pivotally movable lever handle and cam, a pivotally mounted die holder and a handle-mounted head casting which supports punch mechanism. The lever handle travels a substantial distance relatively to the handle of the head casting for thepurpose of transmitting a short powerful cutting movement of the die holder toward the punch to perform the cutting operation on metal between said parts, whereas only a relatively short handle movement results in spacing the punch mechanism from the pivotally mounted die holder to provide ample space between said cutting tools for reception of the metal sheets or channels to be cut. For example, in one embodiment of the invention, the lever handle travels 14 inches from the head casting handle to actuate the die holder to produce 1/4 inch cutting movement, whereas only 4 inches of handle movement separates the die holder from the punch mechanism 2 inches for reception between them of the metal to be cut.

' Another object of the invention is to provide cam means on the pivotally mounted lever handle for engaging the die holder and moving said holder into metal cutting position relatively to the punch means on the head casting.

Another object is to provide means on the die holder frictionally engaging the cam at the end of the cutting stroke for the purpose of retaining the movable handle in closed position adjacent to the handle of the head casting until said movable handle is manually moved away from said head casting handle.

Another object of the invention is to provide an ejector in the head casting for raising a stripper sleeve at the end of the cutting operation. The stripper sleeve is part of the punch mechanism supported on the head casting.

In the drawings:

FIG. 1 is an elevational side view of a hand lever metal punch embodying my invention, showing the parts in the closed or cutting positions.

FIG. 2 is an elevational side view of the punch, partly in section, showing the parts in open non-cutting positions, with the handles partly broken away.

FIG. 3 is a transverse sectional view, on an enlarged scale, in the plane of the. line 3-3 of FIG. 1.

FIG. 4 is an elevational end view of the die holder and punch parts, on an enlarged scale, in the position of the parts as shown in FIG. 1.

FIG. 5 is a fragmentary side elevational view of the cam and associated parts in the cutting positions of the tool, on an enlarged scale, showing the radii of the working surface of the cam.

' In the embodiment of the invention shown in the drawings, the punch body comprises a head casting ll, fixedly connected to a rigid handle 12 terminating in a tubular grip 13. The head casting 11 includes a projecting body 14 provided with a fiat surface 15 supporting the punch mechanism 16 to be described hereinafter. Below the body 14, the head casting 11 has two parallel spaced apart side plates 17 which provide apertured bearings for a die holder pivot pin 18 and a cam pivot pin 19.

A die holder 20 is pivotally mounted on the pivot pin 18 between the side plates 17 of the head casting 11. The holder 20 comprises a flat base 21 integral with die holder side plates 22. The base 21 has a circular opening 23 adjacent one end. The opening 23 communicates with a die ring 24 mounted in the base 21 of the holder 20. A roller 25 is rotatably mounted on a pin 26 adjacent the other end of the die holder between the side plates 22. Depending from the base 21 is a tongue 27 best shown in FIG. 2.

The tongue 27 and roller 25 cooperate with a cam 30 pinned to the lever handle 31 by a pin 32. The cam 30 is mounted on the pivot pin 19 in the head casting 11. The handle 31 has a hand grip 33 on its free end. The cam 30 comprises two cam plates 30 as shown in FIG. 4. A lift roller 35 is mounted in and extends across the cam plates 30 and is engaged by the tongue 27 as shown in FIG. 2;

The punch mechanism 16 comprises a base 40, a sleeve extending from the base 40, a bolt 41 extending through the sleeve 40' and aligning the sleeve in perpendicular position relatively to the surface 15 on the part 14 of the head casting 11, a spring 42 and stripper sleeve 43. Conventional cutting means 44 are threadingly secured to the end of the bolt 41 adjacent the end of the sleeve 40 for cooperation with the die ring 24 on the die holder 20. At the end of the cutting operation, the spring 42 urges the stripper sleeve 43 in a direction away from the base 40 of the punch cutting mechanism, but to augment the spring action, a stripper lever 45 is pivotally mounted on pin 46, with the lever end 47 engageable by the cam 30, and its other end pivotally connected at 48 to an arm 49 having an end 50 contacting the edge of the stripper sleeve 43 for moving the sleeve from the position of FIG. 1 to the position of FIG. 2.

The operation of the punch is as follows:

As shown in FIG. 2, the handles 12 and 31 are spread apart, the die holder 20 has been moved pivotally so that the die ring 24 is spaced from the punch mechanism 16, thereby providing ample space between the cooperating punch means for reception of the metal to be cut. The spread apart positions of the handles results in the cam 30 engaging the roller 25 on the die holder 20, with the tongue 27 of the die holder engaging the lift roller 35 of the cam. Thus when the lever handle 31 is moved manually toward the handle 12, the cam 30 is pivotally moved about the pin 19; the cam bears on roller 25 and causes pivotal movement of the die holder 20 about the pivot pin 18, moving the die holder and its die ring 24 into the position of FIG. 1, where the die ring 24 is in cutting position relatively to the mechanism 16. In the position of FIG. 1, the cam 30 has been moved about the pivot 19 by handle and 57 of H0. 5, a slow rise of the cam surface 55 is produced, and this controls the closing of the cutting mechanisms 16 and 24 by 1/4 inch terminal movement of the handle 31. To move the punch parts from the FIG. 1 to the FIG. 2 positions, the lever handle 31 is spaced from the handle 12 to the limit of its movement. Manual movement of the lever handle 31 toward the handle 12 causes the cam 30 to move about the pivot 19 to contact the roller 25 and bring the cutting means into the FIG. 1 position. This is a relatively fast movement over a substantial distance, terminating in the powerful slower 1/4 inch cutting movement. After completion of the cutting, only a short movement of the handle 31 is required to cause the cam to engage the tongue 27 of die holder 20 and to pivot the holder into raised position of its cutting end for providing space between the cooperating parts of the tool to receive the metal to be cut. I claim:

1. A hand lever metal punch capable of cutting or deforming heavy gauge metal comprising a. a head casting fixedly mounting on a handle, b. a die holder pivotally mounted in the head casting,

c. a die mounted in one end of the die holder,

d. punch mechanism mounted on the head casting for cooperation with the die on the die holder,

e. a manually operable lever handle pivotally connected to the head casting,

f. a cam pinned to the lever handle and pivotally connected to the head casting,

g. means on the die holder engaged by the cam when the lever handle is moved toward the head casting handle to move the die into contact with the punch mechanism on the head casting, and

h. means on the die holder engaged by the cam when the lever handle is moved away from the head casting handle to raise the die carrying end of the die holder and space it from the punch mechanism on the head casting.

2. The tool defined by claim 1, in which the means engaged by the cam for moving the die into contact with the punch mechanism on the head casting is a roller rotatably mounted in the dieholder.

3. The tool defined by claim 1, in which the means engaged by the cam for raising the die holder and spacing it from the punch mechanism on the head casting is a tongue on the die holder.

4. The tool defined by claim 1, in which the working surface of the cam is spaced from the pivotal connection between the cam and the head casting by different radii measured at opposite ends of said working surface, whereby a short powerful movement is transmitted to the die holder and die relatively to the punch mechanism on the head casting.

5. The tool defined by claim 4, in which the difference in radii of the cam equals the distance traveled by the die in metal cutting or deforming movement relatively to the punch mechanism.

6. The tool defined by claim 2, in which the roller mounted in the die holder is frictionally engaged by the working surface of the cam when the lever handle and head casting handle are in the closed positions.

7. The tool defined by claim 3, in which the cam is provided with a lift roller which engages the tongue on the die holder for spacing the die holder from the punch mechanism.

8. The tool defined by claim I, in which the cam comprises a pair of parallel spaced apart side plates and the die holder comprises a pair of parallel spaced apart side plates between which said cam side plates have pivotal movement.

9. The tool defined by claim 1, in which the punch mechanism includes a coiled spring on a bolt having cutting means on one end, a stripper sleeve surrounding the spring and bolt, a stripper lever pivotally mounted on the head casting, and an arm pivotally connected at one end to one end of the stripped lever, the

other end of the stripper lever being actuated by thecam for moving the arm into contact with the stripper sleeve and moving the sleeve on said spring and bolt. 1: 

1. A hand lever metal punch capable of cutting or deforming heavy gauge metal comprising a. a head casting fixedly mounting on a handle, b. a die holder pivotally mounted in the head casting, c. a die mounted in one end of the die holder, d. punch mechanism mounted on the head casting for cooperation with the die on the die holder, e. a manually operable lever handle pivotally connected to the head casting, f. a cam pinned to the lever handle and pivotally connected to the head casting, g. means on the die holder engaged by the cam when the lever handle is moved toward the head casting handle to move the die into contact with the punch mechanism on the head casting, and h. means on the die holder engaged by the cam when the lever handle is moved away from the head casting handle to raise the die carrying end of the die holder and space it from the punch mechanism on the head casting.
 2. The tool defined by claim 1, in which the means engaged by the cam for moving the die into contact with the punch mechanism on the head casting is a roller rotatably mounted in the die holder.
 3. The tool defined by claim 1, in which the means engaged by the cam for raising the die holder and spacing it from the punch mechanism on the head casting is a tongue on the die holder.
 4. The tool defined by claim 1, in which the working surface of the cam is spaced from the pivotal connection between the cam and the head casting by different radii measured at opposite ends of said working surface, whereby a short powerful movement is transmitted to the die holder and die relatively to the punch mechanism on the head casting.
 5. The tool defined by claim 4, in which the difference in radii of the cam equals the distance traveled by the die in metal cutting or deforming movement relatively to the punch mechanism.
 6. The tool defined by claim 2, in which the roller mounted in the die holder is frictionally engaged by the working surface of the cam when the lever handle and head casting handle are in the closed positions.
 7. The tool defined by claim 3, in which the cam is provided with a lift roller which engages the tongue on the die holder for spacing the die holder from the punch mechanism.
 8. The tool defined by claiM 1, in which the cam comprises a pair of parallel spaced apart side plates and the die holder comprises a pair of parallel spaced apart side plates between which said cam side plates have pivotal movement.
 9. The tool defined by claim 1, in which the punch mechanism includes a coiled spring on a bolt having cutting means on one end, a stripper sleeve surrounding the spring and bolt, a stripper lever pivotally mounted on the head casting, and an arm pivotally connected at one end to one end of the stripped lever, the other end of the stripper lever being actuated by the cam for moving the arm into contact with the stripper sleeve and moving the sleeve on said spring and bolt. 